code: def outline_distance(self, bubble, bubbles):
      center_distance = self.center_distance(bubble, bubbles)
      return (
          center_distance
          - bubble[2]
          - bubbles[:, 2]
          - self.bubble_spacing
      )
  
file_path: matplotlib/galleries/examples/misc/packed_bubbles.py
imports: import matplotlib.pyplot
  import numpy
label_desc: Use image node_id 4 for calling the BubbleChart obj's underlying member method code with example usage: obj.outline_distance(bubble, bubbles) and returns: unknown